Improvement in tackle-block sheaves



UNITED STATES PATENT OFFICE..

JOSEPH W. NORCROSS, OF MIDDLETOWN, CONNECTICUT.

IMPROVEMENT IN TACKLE-BLOCK lSHEAVES.

Specification forming part of Letters Patent N0. 56,087, dated July 3, 1866.

To all 'whom 'it may concern Be it known that I, JOSEPH W. NoRoEoss, of Middletown, Middlesex county, State of Connecticut, have invented a new and useful Improvement in Tackle-Block Sheaves; and I do hereby declare that the following is a full, clear, and exact description thereof, which will enable others skilled in the art to make and use the same, reference being had to the accompanying` drawings, forming part of this specification, in which- Figure l represents a transverse section of this invention. Fig. 2 is a side elevation of the same, partly in section.

Similar letters of reference indicate like parts.

` and desirable sheave is produced, Which combines the advantages of ordinary metal sheaves With those of ordinary Wooden sheaves.

A represents a sheave composed of a metal pulley, B,` and Wooden cheeks C. The pulley B is cast of iron, brass, or other suitable material, with a grooved rim, a, which connects by four (more or less) arms, b, with the central hub, c. The rim a is provided With tWo shoulders, d, Which serve to support the cheeks C, which are turned or otherwise produced of Wood. Suitable projections or spurs e are applied on the inner circumference of the rim a, and after the cheeks have been adjusted in the desired position these projections or spurs are turned down over their edges, so as to unite the same firmly and securely with the metal pulley.

By these means I am enabled to produce a sheave which combines the advantages of ordinary iron and Wooden sheaves. It is strong and durable and not liable to Wear out, and it can be made sufficiently large to Work easy Without being too heavy, \vhereas iron sheaves of the ordinary construction, when made large enough to Work easy, become altogether too heavy to be put on vessels aloft, and wooden pulleys, even if bushed With metal, Wear out in a short time.

My sheave can be made of such a size that it works comparatively slow on the center4 pin, and that it is easy for the rope, which has to conform to its circumference, and yet it is light enough to be used on any place Where sheaves are generally used.

What I claim as new, and desire to secure by Letters Patent, is-

A sheavel composed of a metal pulley, B, and Wooden cheeks, as a new article of manufacture, when composed of the shoulders d or the rim a, to support the cheeks C, and the projections or spurs e on the rim, to retain the cheeks in position, substantially as described. Y

JOSEPH W. NORCROSS. Witnesses:

WM. F. MGNAMARA, W. HAUEF. 

